Slide-valve for steam-engines



Patented April 20,1880.

UNITED STATES PATENT OFFICE.

ROBERT E. CARTER, OF PITTSBURG, PENNSYLVANIA.

SLIDE-VALVE FOR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent No. 226,715, dated April 20, 1880.

Application filed February 13, 1880.

To all whom it may concern:

Be it known that I, RoBERT H. CARTER, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Slide-Valves for Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawing, which form part of this specification.

.My invention relates to an improvement in steam-engines; and it consists in the application of a slide-valve to the exhaust of the cylinder which valve is operated by the engine. The said valve opens and shuts alternately the escape-pipe and a pipe leading to a vacuum- Chamber, in which the steam remaininginthe cylinder is condensed, as will be fully described hereinafter.

The accompanying drawing represents my invention. A represents a box containing a slide-valve, B, that may be of any suitable form or construction. The valve is held in its position and connected with the motive power by rods to b, that are guided in holes at the ends of the box, allowing the valve to move from side to side, so as to alternately close and open the lower ends of two pipes, G and D.

The valve B is acted upon by the engine, and allows the steam to escape to the atmosphere through the pipe 0, while the pipe D, leading to the vacuum chamber or condenser, is closed.

The connection between the cylinder of the engine and the box A is made by means of a pipe, E, for the passage of the exhaust-steam from the cylinder. By the returned action of the engine the valve closes the escape-pipe O and opens the pipe D, communicating with the vacuum chamber or condenser.

Acted upon by the vacuum, the steam remaining in the cylinder behind the piston rushes suddenly up into the condenser and is condensed, whereby the resistance to the returning piston is removed.

The advantage gained by my invention is that all the remaining steam in the cylinder, after the greater mass has been allowed to escape, is condensed, and instead of resisting the returning motion of the piston, rat-her assists it by the vacuum created.

A steam-engine, be it of high or low pressure, can thus be worked to its full capacity, and if in a low pressure or condensing engine the surplus steam be allowed to escape and only the steam remaining in the cylinder be condensed, the size of the vacuum-chamber and air-pumps and the quantity of water required to produce'a vacuum may be greatly reduced.

I am aware that a slide-valve having a number'of openings throughit, and which openings are made to register with others in the frame, is not new, and this I. disclaim.-

I am also aware that a vertically moving valve placed at the junction of two pipes is not new, and this I also disclaim.

Having thus described my invention, I claim- In a steam-engine, the combination of an inclosing-case, A,provided with a cover, in which the three pipes O D E are formed in a single piece, with the slide-valve B, having a recess in its top sufficiently long to be always in communication with the central pipe, E, and the one C or D, substantially as shown.

In testimony that I. claim the foregoing I have hereunto set my hand this 7th day of February, 1880.

I ROBT. H. CARTER. Witnesses:

T. 13. LEHMANN,

OHAs. H. ISHAM. 

